Colorectal Quiz Episode 14: ARM Newborn Part 3

A cross-table lateral film (also called crossfire film) is obtained by placing the baby prone in the NICU and shooting a crossfire X-ray; the old fashioned version was an invertogram.

Cross-table lateral films can be obtained early and then around 24 hours later in cases where there is no evidence of fistula on exam.

If the air column stops at about the 4th sacral vertebral body with a large distance between the air column and the sphincter marker, the patient should be considered for diversion and distal colostogram to delineate anatomy.

When the air column is very close to where the anticipated anal opening should be located, primary anoplasty may be performed.

A cross-table lateral film showing air column stopping at approximately the 4th sacral vertebral body with large distance to sphincter is almost definitely a rectal urethral fistula worthy of colostomy.

A cross-table lateral film showing air column very close to the anticipated anal opening is probably almost a perineal fistula or no fistula, and may be appropriate for primary repair, but one must be careful as it might be a low bulbar fistula.

For every patient with anorectal malformation, one should know the type of malformation, the quality of the sacrum, and the quality of the spine.

High malformation, poor sacrum, poor spine indicates not good continence potential; low malformation, normal sacrum, normal spine indicates good potential for bowel control, with many gradations in between.

The PCPLC consortium is calculating data across 15 centers to develop predictions where malformation type, sacral ratio, and spine status can predict continence percentage.

Whether to perform primary anoplasty in cases with close air column depends on individual surgeon comfort and the level of post-operative care available at the institution.

In a male patient where the fistula opening is in the sphincter but in the northernmost part of the sphincteric ellipse, posterior rectal wall only mobilization should be performed, avoiding any anterior wall mobilization to remove the risk of urethral injury.

The common wall between the rectum and the urethra is closer and longer than some people anticipate.

When a fistula opening is in the sphincter but just the most anterior portion, one does not need to dissect or even touch the anterior rectal wall.

A patient at 24 hours with no obvious fistula and cross-table lateral showing air column not very distal needs a colostomy.